Income Taxes (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
	Jan. 01, 2017	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
New Accounting Pronouncements
Income tax expense (benefit)		$ 80	$ 69	$ 92	$ 80
Uncertain income tax positions recorded				$ 0	$ 0
Accounting Standards Update 2016-09 | Adjustment
New Accounting Pronouncements
Income tax expense (benefit)	$ 0
Deferred tax assets	7,300
Deferred tax assets, valuation allowance	7,300
Net deferred tax assets	$ 0